I think you answered your own question. If you upgraded from 120 watts to
255 watts without adding CO2, that's probably as far as you need to look.
Adding additional nutrients without giving your plants a reliable carbon
source is only making your problem worse. If you absolutely cannot add CO2
right away, then I'd start by reducing hours of lighting, probably to ten
hours or so to start. Also, crank back your thermostat to the lowest
possible temperature your fish will tolerate.

DIY CO2 is cheap and you can have it in your tank within an hour, probably
with stuff you've already got lying around the house. Even if you intend to
put a pressurized system in later, I'd get something/anything in there right
away before your plants are ruined. I use two soda bottles on my 75 gallon
(but only 190 watts) with good results.

Anything between 5000k and 7000k is an excellent temp for plant growth
(although you've already noticed that it yellows-out your fish).

Please post your chemistry stats - including ammoniumnitritenitrate - and
let some of the more knowledgeable pros respond to that. Also, temperature,
hours of lighting, algae eaters, etc.

kush

"You can't have everything - where would you put it?"

kgrosnik wrote in message
news:1038841460.311822@sj-nntpcache-3...
Help!!

Need some guidance from those who are successfully managing a fresh
planted
tank.

Problem: No plant growth, algae covered.

What I have: 75g 48"L x 20"H x 18 D. Flourite/gravel mixture substrate,
(2)
metal halide 175w 6500k/(2) 40 w flourecent plant bulbs.

I know the first answer is get a co2 setup, but I had better luck with (3)
40w flourecent bulbs over the metal halides. Should I use a different
spectrum of light such as 10k? Surely with 350w + 80w light would be
sufficient. (doesn't look very bright, yellow tint, 6500k bulbs) The
bulbs
are about 8-10 in above the surface of the water. I have no problems with
the fish stock . Can get ph, O2,CO2 readings, if needed, but I think I've
got a bigger problem. I tried adding pottasium, iron and liquid CO2 on a
regular basis, but it doesn't do anything. Any assistance would be
appreciated.